/*******************************************************************************
 * Copyright (c) 2011 Luaj.org. All rights reserved.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 ******************************************************************************/
package org.luaj.lib.jse;



import org.luaj.Varargs;
import org.luaj.lib.VarArgFunction;
import org.luaj.lib.jse.CoerceLuaToJava.Coercion;

import java.lang.reflect.Array;

import static org.luaj.lib.jse.CoerceLuaToJava.SCORE_UNCOERCIBLE;

/**
 * Java method or constructor.
 * <p>
 * Primarily handles argument coercion for parameter lists including scoring of compatibility and
 * java varargs handling.
 * <p>
 * This class is not used directly.
 * It is an abstract base class for {@link JavaConstructor} and {@link JavaMethod}.
 *
 * @see JavaConstructor
 * @see JavaMethod
 * @see CoerceJavaToLua
 * @see CoerceLuaToJava
 */
abstract
class JavaMember extends VarArgFunction {

    static final int METHOD_MODIFIERS_VARARGS = 0x80;

    final Coercion[] fixedargs;
    final Coercion varargs;
    private Coercion vararg2;
    private Class varclass;

    protected JavaMember(Class[] params, int modifiers) {
        boolean isvarargs = ((modifiers & METHOD_MODIFIERS_VARARGS) != 0);
        fixedargs = new CoerceLuaToJava.Coercion[isvarargs ? params.length - 1 : params.length];
        for (int i = 0; i < fixedargs.length; i++)
            fixedargs[i] = CoerceLuaToJava.getCoercion(params[i]);
        varargs = isvarargs ? CoerceLuaToJava.getCoercion(params[params.length - 1]) : null;
        if (isvarargs) {
            varclass = params[params.length - 1].getComponentType();
            vararg2 = CoerceLuaToJava.getCoercion(varclass);
        }
    }

    int score(Varargs args) {
        int n = args.narg();
        int s = 0;
        if (n < fixedargs.length)
            return CoerceLuaToJava.SCORE_UNCOERCIBLE;
        if (n > fixedargs.length) {
            if (varargs == null)
                return CoerceLuaToJava.SCORE_UNCOERCIBLE;
            else
                s = CoerceLuaToJava.SCORE_WRONG_TYPE;
        }
        for (int j = 0; j < fixedargs.length; j++) {
            s += fixedargs[j].score(args.arg(j + 1));
            if (s > SCORE_UNCOERCIBLE)
                return s;
        }
        if (varargs != null) {
            if (n == fixedargs.length + 1) {
                s += Math.min(varargs.score(args.arg(fixedargs.length + 1)), vararg2.score(args.arg(fixedargs.length + 1)));
            } else {
                for (int k = fixedargs.length; k < n; k++)
                    s += vararg2.score(args.arg(k + 1));
            }
        }
        return s;
    }

    protected Object[] convertArgs(Varargs args) {
        Object[] a;
        if (varargs == null) {
            a = new Object[fixedargs.length];
            for (int i = 0; i < a.length; i++)
                a[i] = fixedargs[i].coerce(args.arg(i + 1));
        } else {
            int n = args.narg();
            a = new Object[fixedargs.length + 1];
            for (int i = 0; i < fixedargs.length; i++)
                a[i] = fixedargs[i].coerce(args.arg(i + 1));
            if (n == fixedargs.length + 1) {
                if (varargs.score(args.arg(fixedargs.length + 1)) < vararg2.score(args.arg(fixedargs.length + 1)))
                    a[fixedargs.length] = varargs.coerce(args.arg(fixedargs.length + 1));
                else
                    a[fixedargs.length] = vararg2.coerce(args.arg(fixedargs.length + 1));
            } else {
                int m = Math.max(args.narg() - fixedargs.length, 0);
                Object v = Array.newInstance(varclass, m);
                for (int i = fixedargs.length; i < n; i++)
                    Array.set(v, i - fixedargs.length, vararg2.coerce(args.arg(i + 1)));
                a[fixedargs.length] = v;
            }

			/*int n = Math.max(fixedargs.length,args.narg());
			a = new Object[n];
			int m = Math.max(args.narg()-fixedargs.length,0);
			Object v = Array.newInstance(varclass, m);
			for ( int i=0; i<fixedargs.length; i++ )
				a[i] = fixedargs[i].coerce( args.arg(i+1));
			for ( int i=fixedargs.length; i<n; i++ )
				//a[i] = varargs.coerce( args.arg(i+1) );
			    Array.set(v,i-fixedargs.length, varargs.coerce( args.arg(i+1)));
			a[fixedargs.length]=v;*/
        }
        return a;
    }
}
